Chinese government-sponsored hackers have been targeting US companies and government agencies for years. Even when called out on it, China continues to try and eke out as much information as possible.

Until now though, most people believed the stolen data had to do with proprietary software, hardware design, and so on. The Chinese also targeted the accounts of dissidents and critics.

But there's more to it. The Washington Post, citing sources in the government, revealed that the Chinese may have gotten much more than the source code to Gmail in the Google breach of a few years ago.

That's the attack that pushed Google out of China, claiming that it did not want to do business in a country in which censorship is rampant.

Hackers may have gotten access to a year's worth of logs on US surveillance targets. US law enforcement agencies regularly request access to user accounts from Google, and the number of requests is revealed by Google in its transparency report every six months.

The Chinese were interested in the data, as it could have revealed whether agencies were investigating Chinese agents infiltrated in US companies or the administration.

This would have enabled the Chinese to know whether the identity of any of their agents was compromised or not. It also made it possible to feed false information to the US agencies through the emails of agents China knew were compromised.

The US government knew about this, of course, and a lot more probably. Yet it hasn’t done much, at least not publicly, to thwart the Chinese attacks.